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Progress in Manufacturing Sustainability

Green is Good

By Ellen KehoeSenior Editor, Journals & Technical Papers

Sustainable manufacturing approaches, standards initiatives and industry solutions were highlighted at a panel session June 13 at the NAMRC-MSEC advanced manufacturing conference, an annual event of the North American Manufacturing Research Institution of SME and the Manufacturing Engineering Division of ASME. The University of Wisconsin-Madison hosted the conference June 10-14, with more than 400 academic, government and industry researchers and manufacturing leaders attending.The panel was led by Kevin Lyons, group leader, life cycle engineering, National Institute of Standards and Technology (NIST; Gaithersburg, MD), and David Dornfeld, professor and director, Laboratory for Manufacturing and Sustainability (LMAS), University of California-Berkeley, and emphasized the collective and consistent practice of sustainability for beneficial impact, that is, a common outlook on terminology, methodology, measurement science and tool development.

Michael Overcash, Sam Bloomfield chair in sustainable engineered systems, Wichita (KS) State University, explained that, while supply chain analysis tools are numerous and advanced, the approximately two million US manufacturing plants need tools that are noncomplex, transparent, robust and quantify the contribution or role in the environmental life cycle of a product or product family. Plants also increasingly must show their improvement in energy and materials efficiency.The gate to gate (GTG) part of the product life cycle is the manufacturing plant, where each product/family is a sequence of individual machines, each referred to as a unit process. A unit process life cycle inventory (UPLCI) maps the large number of steps from materials to product, with the analysis estimating energy and material loss in three components—standby or basic mode, idle or partial mode and tip or full mode. Tip energy is widely known, so standby and idle energies are the main focus. UPLCI is a basic screening method in the international effort CO2PE! (Cooperative Effort on Process Emissions), which further includes in-depth machine optimization.

Overcash says UPLCI developers have learned to avoid too much detail at the design level and have found that working on high-production processes reduces extreme results. Energy and mass efficiency results in the UPLCI format are highly credible because engineering and manufacturing aspects are transparent and can be changed. UPLCI is effective in rapid design, new materials and new process benchmarking.

Framework for Sustainability

The larger framework for sustainability is to define the problem, system boundary and scope, establish key performance indicators and build tools to assess sustainability, according to Margot Hutchins, associate director, LMAS, at UC-Berkeley. A comprehensive, holistic approach characterizes manufacturing systems fully, assesses important resource flows across all levels of the hierarchy (process, cell, line, facility) and provides analysis of the role of manufacturing in the entire product life cycle.

Data captured from appropriate system flow sensors are best monitored concurrently with data from process parameters. Standardized data aid synthesis, support analysis across the hierarchy and enable scaling to large data volumes. Relating key process parameters to environmental impacts (energy and water consumption, wastes generated, CO2 emissions); technical performance (tool wear, product quality); and social impacts like human and labor costs and community health and well-being helps characterize product performance in terms of part features. These results are combined into the cost function of resources, services and products to select the process parameters that optimize the product life cycle, providing new opportunities for optimization and improvement.

At Briggs & Stratton Corp. (Milwaukee) locations throughout the world, sustainability and energy teams are embedded as a culture attribute. John Mourand, corporate environmental and sustainability director, talked about the many lifecycle assessments (LCAs) the company conducts each year to understand the environmental impact of its products—from raw materials extraction and processing, manufacturing and transportation to in-service use through to disposal.

In one example, handling aluminum scrap was transitioned from a recycling process to a reuse operation by forming aluminum chips into “pucks” and putting them back into the melt furnace onsite. The reuse process saved handling and transportation costs (i.e., 125 truck shipments) associated with recycling, leading to Mourand’s statement that “recycling is good, reusing is great.”

Sustainability Good for Hiring

Caterpillar Inc. (Peoria, IL) focuses about 47% of its efforts on facilities-related improvements and 53% on manufacturing efficiency. According to Karen Huber, division manager, manufacturing technology research and development, long-term goals are meeting Leadership in Energy and Environmental Design (LEED) or comparable green building criteria, holding water consumption flat, reducing greenhouse gas emissions by 25% and increasing energy efficiency by 25%.Caterpillar is finding new ways reduce, reuse, recycle and reclaim materials that once would have gone into a landfill. For example, last year, remanufacturing at Caterpillar (Cat Reman) took back more than 2.2 million end-of-life units and remanufactured over 161 million lbs (73028 T) of material.

Advanced data capture and simulation help in understanding facilities and modeling manufacturing value streams to reduce energy, fuel, power, waste, cost and time. The bottom line, Huber says, is that goals are accomplished by employees, research and customers working together. Sustainable manufacturing is also a competitive advantage from Caterpillar’s perspective. Public interest and customer feedback on sustainability drives a positive corporate image, which in turn is a good recruiting tool. “People want to work for a company that is working on recycling.”

Focus on Standards

Autodesk’s Sarah Krasley, manufacturing program manager, sustainability solutions, urged the manufacturing community to give input on the standardization compliance process, for example to NIST. Autodesk (San Rafael, CA) is involved with several organizations and councils for standards efforts and joint technology development.

For green design, an example is the Eco Materials Adviser, which is included with Autodesk® Inventor® software and accesses a materials database cloud-hosted by Granta Design Ltd. (Cambridge, UK). The Eco Materials Adviser helps designers and engineers run simulated trials of different materials to identify cost savings, energy use, waste reduction, recyclability, regulatory requirements and so on. Reports help engineers communicate the benefits of sustainable design decisions.Go to usa.autodesk.com/sustainable-design for reports, industry solutions and more information.

A roundtable discussion following the individual presentations encouraged standards development and reliable measurement methods, metrics and guidance to evaluate manufacturing process-related sustainability performance.

Founders Lecture Reviews Sustainability Milestones

The NAMRC Founders Lecture, given by Delcie R. Durham, PhD, FSME, PE, of the University of South Florida (Tampa), on June 12 also addressed sustainable, scalable manufacturing and its evolution over the past 30 years. Durham echoed the presentations by authors and panelists in stating the need for definitions, methods and tools, metrics and standards, industrial implementation and “K-gray” education.

For the definition, she likened the pillars of sustainability—economy, nature and society—to a three-legged stool, with manufacturing sitting on top. Industrial environmental performance metrics have improved from being nonexistent before 1970, reactive from the 1970s to the 1990s, anticipatory in the 1990s and, finally, integrated with design since 2000. Likewise, during Durham’s time at the National Science Foundation in the 1990s, there were few grant applicants for environmental research because no one thought manufacturing could be environmentally benign.